135 research outputs found

    Energy flow in a hadronic cascade: Application to hadron calorimetry

    Get PDF
    The hadronic cascade description developed in an earlier paper is extended to the response of an idealized fine-sampling hadron calorimeter. Calorimeter response is largely determined by the transfer of energy EeE_e from the hadronic to the electromagnetic sector via π0\pi^0 production. Fluctuations in this quantity produce the "constant term" in hadron calorimeter resolution. The increase of its fractional mean, f_{\rm em}^0 = \vev{E_e}/E, with increasing incident energy EE causes the energy dependence of the π/e\pi/e ratio in a noncompensating calorimeter. The mean hadronic energy fraction, fh0=1fem0f_h^0 = 1-f_{\rm em}^0, was shown to scale very nearly as a power law in EE: fh0=(E/E0)m1f_h^0 = (E/E_0)^{m-1}, where E01E_0\approx1 GeV for pions, and m0.83m\approx0.83. It follows that π/e=1(1h/e)(E/E0)m1\pi/e=1-(1-h/e)(E/E_0)^{m-1}, where electromagnetic and hadronic energy deposits are detected with efficiencies ee and hh, respectively. Fluctuations in these quantities, along with sampling fluctuations, are incorporated to give an overall understanding of resolution, which is different from the usual treatments in interesting ways. The conceptual framework is also extended to the response to jets and the difference between π\pi and pp response.Comment: This paper extends to HEP calorimetry the conceptual framework developed in Gabriel, Groom Job, Mokhov, and Stevenson, "Energy dependence of hadronic activity," NIM A 338 (1994) 336-34

    Simplification of the DREAM collaboration's "Q/S method" in dual readout calorimetry analysis

    Full text link
    The DREAM collaboration has introduced the "Q/S Method" for obtaining the energy estimator from simultaneous Cherenkov and scintillator readouts of individual hadronic events. We show that the algorithm is equivalent to an elementary method

    Muon stopping power and range tables 10 MeV-100 TeV

    Get PDF
    The mean stopping power for high-energy muons in matter can be described by −dE/dx = a(E) + b(E)E, where a(E) is the electronic stopping power and b(E) is the energy-scaled con-tribution from radiative processes—bremsstrahlung, pair production, and photonuclear interac-tions. a(E) and b(E) are both slowly-varying functions of the muon energy E where radiative effects are important. Tables of these stopping power contributions and continuous-slowing-down-approximation (CSDA) ranges (which neglect multiple scattering and range straggling) are given for a selection of elements, compounds, mixtures, and biological materials for incident kinetic en-ergies in the range 10 MeV to 100 TeV. Tables of the contributions to b(E) are given for the same materials

    Towards a Roadmap for Advancing the Catalogue of the World’s Natural History Collections

    Get PDF
    Natural history collections are the foundations upon which all knowledge of natural history is constructed. Biological specimens are the best documentation of variation within each species, increasingly serve as curated sources for reference DNA, and are frequently our only evidence for historical species distribution. Collections represent an enormous multigenerational investment in research infrastructure for the biological sciences, but despite this importance most of the holdings of these institutions remain invisible on the Internet, inaccessible to taxonomists from other countries and hidden from computational biodiversity research.Although comprehensive digitisation of the complete holdings of each natural history collection is the long-term goal, this is an expensive and labor-intensive task and will not be completed in the near future for all collections. However, many benefits could quickly be achieved by publishing high-quality metadata on each collection to increase its visibility, provide the foundations for further digitisation and enable researchers to discover and communicate with collections of interest.This paper summarises the results from a consultation activity carried out in 2020 as part of the SYNTHESYS+ (Synthesys of Systematic Resources), “Developing implementation roadmaps for priority infrastructure areas as part of cooperative RI for biodiversity” project. This consultation was primed through an ideas paper, and introductory webinars and conducted as a facilitated two-week online multilingual discussion around 26 topics grouped under four broad headings (Users, Content, Technology and Governance). The results of these discussions are summarised here, along with the wider context of existing and planned initiatives

    Experimental Bounds on Masses and Fluxes of Nontopological Solitons

    Get PDF
    We have re-analyzed the results of various experiments which were not originally interested as searches for the Q-ball or the Fermi-ball. Based on these analyses, in addition to the available data on Q-balls, we obtained rather stringent bounds on flux, mass and typical energy scale of Q-balls as well as Fermi-balls. In case these nontopological solitons are the main component of the dark matter of the Galaxy, we found that only such solitons with very large quantum numbers are allowed. We also estimate how sensitive future experiments will be in the search for Q-balls and Fermi-balls.Comment: 19 pages, 7 eps figures, RevTeX, psfig.st

    Community engagement: The ‘last mile’ challenge for European research e-infrastructures

    Get PDF
    Europe is building its Open Science Cloud; a set of robust and interoperable e-infrastructures with the capacity to provide data and computational solutions through cloud-based services. The development and sustainable operation of such e-infrastructures are at the forefront of European funding priorities. The research community, however, is still reluctant to engage at the scale required to signal a Europe-wide change in the mode of operation of scientific practices. The striking differences in uptake rates between researchers from different scientific domains indicate that communities do not equally share the benefits of the above European investments. We highlight the need to support research communities in organically engaging with the European Open Science Cloud through the development of trustworthy and interoperable Virtual Research Environments. These domain-specific solutions can support communities in gradually bridging technical and socio-cultural gaps between traditional and open digital science practice, better diffusing the benefits of European e-infrastructures

    In-reach specialist nursing teams for residential care homes : uptake of services, impact on care provision and cost-effectiveness

    Get PDF
    Background: A joint NHS-Local Authority initiative in England designed to provide a dedicated nursing and physiotherapy in-reach team (IRT) to four residential care homes has been evaluated.The IRT supported 131 residents and maintained 15 'virtual' beds for specialist nursing in these care homes. Methods: Data captured prospectively (July 2005 to June 2007) included: numbers of referrals; reason for referral; outcome (e.g. admission to IRT bed, short-term IRT support); length of stay in IRT; prevented hospital admissions; early hospital discharges; avoided nursing home transfers; and detection of unrecognised illnesses. An economic analysis was undertaken. Results: 733 referrals were made during the 2 years (range 0.5 to 13.0 per resident per annum)resulting in a total of 6,528 visits. Two thirds of referrals aimed at maintaining the resident's independence in the care home. According to expert panel assessment, 197 hospital admissions were averted over the period; 20 early discharges facilitated; and 28 resident transfers to a nursing home prevented. Detection of previously unrecognised illnesses accounted for a high number of visits. Investment in IRT equalled £44.38 per resident per week. Savings through reduced hospital admissions, early discharges, delayed transfers to nursing homes, and identification of previously unrecognised illnesses are conservatively estimated to produce a final reduction in care cost of £6.33 per resident per week. A sensitivity analysis indicates this figure might range from a weekly overall saving of £36.90 per resident to a 'worst case' estimate of £2.70 extra expenditure per resident per week. Evaluation early in implementation may underestimate some cost-saving activities and greater savings may emerge over a longer time period. Similarly, IRT costs may reduce over time due to the potential for refinement of team without major loss in effectiveness. Conclusion: Introduction of a specialist nursing in-reach team for residential homes is at least cost neutral and, in all probability, cost saving. Further benefits include development of new skills in the care home workforce and enhanced quality of care. Residents are enabled to stay in familiar surroundings rather than unnecessarily spending time in hospital or being transferred to a higher dependency nursing home setting
    corecore